Born
of a need
to have an AC load controlled by an IBM i-Series (AS/400) the Corkwerks
400 takes a standard parallel printer input and provides 2 separate
sets
of relay contacts and a switched AC output. A guarded front panel
momentary
switch allows for manual control of the outputs. Standard connectors
are
used throughout to make installation as simple as possible.

A single LED lighted switch on
the front panel
indicates when the relays are active and provides a means of
manually
actuating the relays

A standard IEC power cord
provides AC voltage
to the unit through a master switch and a resettable circuit breaker.
An
internal MOV (Metal Oxide Varistor) provides surge protection for the
unit
in additional to any external surge strip or line conditioning device.
The 5 volt DC supply inside is additionally fuse protected on the
circuit
board.

A standard parallel printer
connector (Centronics
36 pin) allows the use of any ordinary printer cable for the control
connection.

A solid state relay provides
switched AC voltage
to a standard AC socket on the back panel up to 10 amps.

Interfacing
to the IBM
i-Series (AS/400)

This design
originated
from a need to control production floor buzzers from the AS/400 to
synchronize
with time and attendance collections. Maximum flexibility was also
desired
for future buzzer system changes. With the selection of outputs the
Corkwerks
400 is not limited to buzzer operation and models utilizing all 8 data
lines in the parallel interface are possible.

In the buzzer
application
a remote PC (actually a time and attendance collection point) is
connected
to the Corkwerks 400. IBM's Client Access PC software has the capacity
to accept incoming remote commands from the AS/400 to run specified
programs.
A scheduled process on the AS/400, using the same system time as the
data
collection points, passed a run command to the clock PC. The PC
application
simply prints a character to the parallel printer port for a
predetermined
length of time or a time parameterized by the AS/400 process calling
the
PC application.

The AS/400
system is
isolated from the AC load by the network connection to the PC and
further
by the printer port and the isolation of the Corkwerks 400's internal
relays.